1. Field of the Invention
The invention relates to carpet seaming irons in general and in particular to a carpet seaming iron with an ultra thin guide strut for minimizing the separation of carpet edges during the seaming thereof, improved guiding of the iron between the seams and more efficient heat control for better adhesion of the carpet to thermally sensitive carpet tape.
2. Description of the Prior Art
A carpet seaming iron is used to join and form an invisible seam between adjacent edges of a carpet during the installation of two or more pieces thereof. In practice, a length of thermally sensitive adhesive tape is laid beneath the edges, extending 11/2 to 3 inches on opposite sides thereof. The iron is then moved along the seam beneath the edges of the carpet, heating the tape. As the iron is moved, the carpet edges are closed behind the iron and affixed to the tape.
Typical seaming irons comprise a heating element in a base member having a heat shield on the upper surface thereof and a handle which is rigidly attached to the heat shield. In a conventional iron the handle is relatively thick, i.e. wide, in a direction transverse the longitudinal axis of the iron. The thick handle is found to have a number of disadvantages. For example, during seaming, the edges of the carpet between which the handle is moved are forced apart to the front, sides and rear of the iron. With a thick handle the edges of the carpet behind the iron are separated to such an extent that it is not possible to close them for a considerable distance behind the iron. If the iron is moved too slowly permitting the heated tape to cool, the extensive separation of the carpet edges behind the iron also makes it difficult to get a tight seam with good adhesion to the tape.
To obtain good adhesion, it is important to heat all of the seaming tape. Since the tape lies beneath the carpet edges and therefore is not readily visible to the operator, the operator typically uses the edges of the carpet to help guide the iron so that it is moved over the tape. Unfortunately, another disadvantage of a wide handled iron is that the extent of the upward inclination and separation of the edges of the carpet as the edges are separated by the handle reduces the effect which the edges have on guiding the iron as it is moved over the tape. This makes the operator's job more difficult, resulting sometimes in a failure to heat parts of the tape.
Another disadvantage of conventional seaming irons is their inability to provide proper heating of the tape. Prior known irons typically comprise a tubular fixed temperature heating element which is located adjacent to the sole plate in the base member of the iron. The resulting effect is that the temperature of the sole plate is not uniform. Instead, there is a high temperature along the line of contact of the heating element with the sole plate with a decreasing temperature gradient outwardly therefrom. Also, the temperature is the same along the line of contact from the front to the rear of the iron.
Still another disadvantage of conventional irons is the high heat shield temperature which typically exceeds the melting temperature of most carpet backings, e.g. 300.degree. F.